This specification relates to query suggestions.
The Internet provides access to a wide variety of resources. Example resources include video files, image files, audio files, or Web pages including content for particular subjects, book articles, or news articles. A search system can select one or more resources in response to receiving a search query. A search query is data that a user submits to a search engine to satisfy the user's informational needs. The search system selects and scores resources based on their relevance to the search query and on their importance relative to other resources to provide search results that link to the selected resources. The search results are typically ordered according to the scores, and provided in a search results page.
Search systems can provide search suggestions to users to help users satisfy their informational needs. As used herein, the term “query suggestion” is suggested data that can be used to refine a search or refine a search strategy. A query suggestion can be another search query, keywords, or topics to which a search query or keyword belongs. A query suggestion is often used as an additional query, e.g., the query suggestion can be processed by the search system as a query in response to a user selection of the query suggestion.
Some search systems provide query suggestions as the user is typing so that the user can select a query suggestion without requiring typing the entire query. These systems typically send suggestion requests to a search engine with each keystroke, and the search engine provides query suggestions with prefixes that match the entered characters. This suggestion service is also offered on mobile devices. However, mobile devices often need to deal with much higher network latency, and the performance of the suggestion service can degrade as latency increases. Often the latency may be such that the suggestions received do not match the current query prefix entered, which tends to degrade the user experience rather than improve it.